DSL changes IP when DHCP server is down.

Forum: Networking
Topic: DSL changes IP when DHCP server is down.
started by: magicpio

Posted by magicpio on Dec. 15 2005,21:12

Hi!
My DSL 1.5 box is changing its ip address (previously supplied by a dhcp server) when this server is down.
ifconfig will then show 0.0.0.0 on eth0.

Is there any solution to
- assign a default ip in case
1) there was no dhcp server running during bootup of DSL
2) the server goes down, but DSL box still runs
- DSL trying to renew the lease every x minutes if 1) or 2) applies, so when server is up again, DSL gets a new ip via dhcp?

I tried messing with dhcpd.conf but cannot get my head properly around the options.

Thanks for help.
magicpio

Posted by cbagger01 on Dec. 17 2005,03:51

DSL uses "pump" for the DHCP client.

Lease renewals SHOULD work correctly, but for some reason is not in your case.

Maybe try a static IP address as a workaround?

Posted by larkl on Dec. 17 2005,13:12

Dhcpd.conf is for configuring the dhcp server, not the client. You could add a few lines to your bootlocal.sh file that could handle it. Say your normal IP address range from the dhcp server is 192.168.1.X and that 192.168.1.254 is outside of the range used by the dhcp server and that eth0 is the interface, then

Code Sample

if ifconfig|grep 192.168.1
then exit
else
ifconfig eth0 192.168.1.254
fi

So, if ifconfig contains the IP range you stop, otherwise you set a manual IP. Might not have the commands just right, but you get the drift. After all this, might be easier to just use a static address (as cbagger01 suggests).